Associated calendar with "Greyhawk" subforum (only 1 subforum can be associated with the calendar).
Now, when you click on the word calendar (bottom of calendar widget on the portal page), you go to the calendar, and each date on it has a clickable icon ("Add an Event") which creates a topic in the "Greyhawk" subforum with the date info aleady filled in (see OP).
Not sure if any of this is useful or more convenient than our current method. Using the calendar would mean a separate topic per game night.